Power-Up Failure - Motorola APX 3000 Detailed Service Manual

5-4
5.3 Power-Up Failure – Main Board
Main Board Power Up
Problem
Measure Voltage
at C6593
No
6 < V < 9?
Yes
Measure Voltage
at R6542
No
3.3 < V < 3.9
Yes
Use Oscilloscope
to Measure R6533
No
Freq = 24MHz
1.6 < V < 1.9
Yes
Measure All Probe
Spots from Above
Table
Voltages =
Level
No Yes
Proceed to
Specified Flow
Chart in Table
Name
V_1.55
V_2.775D
V_2.775
V_2.8_RF
V_5.0A
V_3.3
V_3.0A
V_SW_3.6
Proceed to
Incorrect B+
V_EXT_1.85
Voltage Flow
Chart
V_SW_1.4
Proceed to Low
V_SW_3.60
Flow Chart
Repair or Replace Replace Main
Part/s
No
Inspect Y6501 and Are Parts Solder
All supporting Connections and
Circuitry Placement Correct
Use Oscilloscope
Replace Main
Impedance Probe
Board
No
Yes
Use Oscilloscope
1.6 < V < 1.9
to Measure R6115
Measure Voltage
at R6203
Ref Description
R6561 LDO Output
R6562 LDO Output
R6563 LDO Output
R6564 LDO Output
R6565 LDO Output
R6566 LDO Output
R6567 LDO Output
C6561 Switching Output 3.6±10%
R6570 LDO Output
E6502 Switching Output 1.4±10%
Board
Yes
Measure Voltage
at OMAP_RESET_TP
and High
Freq = 12MHz
1.3 < V < 1.9
to Measure
C6602
Yes
Freq = 32kHz
1.6 < V < 1.9
Replace Main
Board
Troubleshooting Charts: Power-Up Failure
Level V
1.55±10% Low LDO3 V_1.55 Voltage
2.775±10% Low LDO10 V_3.3 Voltage
2.775±10% Low LDO10 V_3.3 Voltage
2.8±10% Low LDO10 V_3.3 Voltage
5.0±10% Low LDO8 V_5.0A Voltage
3.3±10% Low LDO10 V_3.3 Voltage
3.0±10% Low LDO10 V_3.3 Voltage
Low V_SW_3.6 Voltage
1.85±10% Low V_1.85 Voltage
Low V_SW_1.4 Voltage
Replace
Main Board
No
OMAP is Out of
Yes Reset, Proceed to
1.6 < V < 1.9
Memory Flow
Chart
Yes
No
Inspect Y6601
Circuit
Are Parts Solder
Connections and
Placement Correct
No
Yes
Repair or Replace
Part/s
Flow Chart
No